Avalanche safety and survivability devices are known. An unaddressed problem is that known safety devices only assist and, in fact, rely upon search and rescue teams coming to aid a victim. That is, they do not, independent of search and rescue operations, improve the survival chances of an individual caught or buried in an avalanche. The present invention incorporates the known effect of gravity on a liquid contained in a partially liquid-filled, sealed container and an illumination source to meet this unaddressed problem.
There are many methods and devices which rely upon the influence of gravity on liquid to display horizontal or vertical orientation or degree of inclination from either. In the building trades for example, such devices take the form of simple bubble or spirit levels. While these devices are well suited for their intended use, for obvious reasons it is impracticable for a person to carry such equipment while engaged in a recreational activity such as skiing or backpacking in an area where avalanches might occur.
Level indicating devices have been applied in some recreational uses. U.S. Pat. No. 4,745,687 discloses a level indication device for use with recreational vehicles. The device comprises a base on which is mounted a liquid containing enclosure carrying a pair of spaced parallel lines. When the surface of the liquid is located between the lines the bottom surface of the base will be within three degrees from level with respect to the horizontal plane. This device is designed to be attached to a recreational vehicle and, again, it would be impractical for a person to use while engaged in a recreational activity such as skiing.
With direct regard to avalanche safety or survivability devices, the long-felt need for such devices is manifested by the profusion of available equipment. Typically, these devices are position-indicating devices designed to be used by persons venturing, either purposefully or by accident, into avalanche-prone areas. If a person carrying one of these devices is caught in an avalanche, the device enables rescue teams to locate the person. This type of equipment includes "break-apart" items such as ski-poles, parts of which, attached to the person or other equipment by a cord or ribbon, may rise to the surface of the snow and be spotted by a rescue team which then follows the cord to the location of the buried person. Balloon, flare or dye-releasing devices are known also, but one of the most commonly used devices is the beacon-generating device. These are well-known in the literature and are well-represented by commercially available transmitting/receiving devices.
The beacon and other location-indicating devices represent years of concern about avalanche survivability and certainly have increased victims' chances for surviving avalanches. However, this type of device has a fundamental limitation. They are predicated on the requirement that an outside agency, i.e., a person or group of persons such as a search and rescue team, will perceive the indication provided by the device, locate and then dig out and assist the victim.
A person caught or buried in an avalanche will be extremely disoriented and, after only a brief period of time, a buried victim's survival chances become very low due to hypothermia, shock or suffocation. Therefore, it is extremely important that a victim quickly learn the direction of the surface and begin to try to reach it. Despite the advances in avalanche safety devices, there remains an unaddressed need for a simple, easily portable, reliable device that an individual caught or buried in an avalanche can use immediately without relying on outside assistance to determine the upward direction and thus increase the chances for surviving.